Modifying the composition of a compressible or non-compressible fluid prior to its ejection from a lumen is a desirable step with numerous far-reaching applications. For example, by modifying a non-compressible fluid prior to its ejection from a lumen, the fluid may be stored in one state and then changed or modified into another state, one that is more useful or beneficial for the task at hand.
With regard to certain medical procedures, it may be advantageous, for example, for a therapeutic being delivered to a target site in the body to rapidly solidify upon its disposition into the target site. In one specific example, when therapeutic is injected into an actively contracting tissue, such as the myocardium of the heart, the therapeutic may be susceptible to being ejected or squeezed back out through its point of entry. This unwanted discharge of the therapeutic can result in an unascertainable dosage of therapeutic being actually administered to the myocardium as well as the unwanted interface between the expelled therapeutic and neighboring tissue and organs. Thus, in order to combat this unwanted discharge solid plugs may be formed encapsulating the therapeutic to retard its ejection from the target site.
While it may be beneficial to employ a therapeutic having a high solids content, therapeutic with a high solid to fluid ratio may resist passage though its delivery lumen. In some cases a solvent may be used to provide an operative balance of solids to fluids. In these cases, however, the solvent employed may be toxic in relation to the delivery site or incompatible with the therapeutic.
When the solvent is toxic it may be toxic in certain applications but not in others. For example, ethanol, which maybe used as a solvent, is generally considered “bio-compatible,” however, this is clearly not the case when the target site is within the myocardium. This selective toxicity is problematic at least to the extent that a medical device carrying a therapeutic could not be universally employed but would, rather, only be usable for target sites that were not injured by the solvent.
To counter this potential toxicity with the target and the unwanted incompatibility with the therapeutic a less than optimum amount of solvent may be used. Alternatively, a proper amount of solvent may be used at the risk of unwanted side effects stemming from its use. In both cases the effectiveness of the therapeutic may be compromised.